The zombie-filled universe which Angstrom crosses into at the end is a nod to Robert Kirkman's other series, 'The Walking Dead'.
Due to scheduling conflicts with Jonathan Groff, Jonathan Groff is unable to reprise Rick Sheridan's voice.
When Mark gets the coffee there are two broken hearts floating on the surface in the cups.
Brothers & Sisters (2006) stars Calista Flockhart and Luke Macfarlane reunite to play April Howsam and Rick Sheridan.